as in treacherous
formal
causing harm in a way that is gradual or not easily noticed
Most people with this insidious disease have no idea that they are infected. an insidious enemy
Synonyms & Similar Words
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Antonyms & Near Antonyms
Example Sentences
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Recent Examples of insidious
But psychological research presents a deeper, more insidious explanation — one that doesn’t just apply to politicians and public figures, but to clinicians, as well.
—
Robert Pearl, Forbes.com, 26 May 2025
Beyond the physical abuse, Cassie endured a steady drumbeat of insidious threats that sent an unmistakable message: the violence could escalate at any moment.
—Lauren Hersh, New York Daily News, 21 May 2025
Here, though, the spectacle of Laura’s darkness is not presented as a slowly unfolding insidious revelation.
—Owen Gleiberman, Variety, 16 May 2025
And that’s indeed already happening, probably in insidious ways that aren’t publicly disclosed.
—Kieran Press-Reynolds, Pitchfork, 14 May 2025
See All Example Sentences for insidious
Robert Pearl, Forbes.com, 26 May 2025
Beyond the physical abuse, Cassie endured a steady drumbeat of insidious threats that sent an unmistakable message: the violence could escalate at any moment.
—Lauren Hersh, New York Daily News, 21 May 2025
Here, though, the spectacle of Laura’s darkness is not presented as a slowly unfolding insidious revelation.
—Owen Gleiberman, Variety, 16 May 2025
And that’s indeed already happening, probably in insidious ways that aren’t publicly disclosed.
—Kieran Press-Reynolds, Pitchfork, 14 May 2025
See All Example Sentences for insidious
Recent Examples of Synonyms for insidious
Adjective
-
The Neshaminy Creek, placid in calm weather, turns treacherous after heavy rains, such as those that fell on Bucks County in the days before his accident.—
JD Mullane,
USA Today,
29 May 2025
-
The savvy financial advisor Rick Kahler, president of Kahler Financial Group in Rapid City, S.D., tells us how to navigate this treacherous path.—
Larry Light,
Forbes.com,
27 May 2025
Adjective
-
The family secrets were subtle but pervasive, reverberating not just through this nuclear family, but also across generations.—
Susan Walter
June 6,
Literary Hub,
6 June 2025
-
Your new album, Faith, is a lot subtler than your debut, Signs.—
Philip Sherburne,
Pitchfork,
6 June 2025
Adjective
-
The decision to deploy Dembele as a false nine for a 3-1 home win over Lyon in mid-December proved the spark for a stupendous run of goal-scoring form in which the France international racked up 27 goals in only 22 appearances.—
Tom Williams,
New York Times,
30 May 2025
-
Their accountant filed two false corporate tax returns, claiming one of the couple’s firms earned no money in 2015 and 2016.—
Howard Gleckman,
Forbes.com,
30 May 2025
Adjective
-
Last year, the Biden administration's Transportation Department opened an inquiry ordering American, Delta Air Lines, Southwest and United to provide records and submit reports to ensure consumers do not face unfair, deceptive, or anticompetitive practices.—
David Shepardson,
USA Today,
3 June 2025
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The quest to build human-level AI agents using techniques known to produce deceptive tendencies, Bengio says, is comparable to a car speeding down a narrow mountain road, with steep cliffs on either side, and thick fog obscuring the path ahead.—
Harry Booth,
Time,
3 June 2025
Adjective
-
Jake Gyllenhaal is his foil as the perfidious Iago, who goads Othello into unreasoning jealousy with lies about his beloved Desdemona (Molly Osborne).—
New York Times,
New York Times,
17 Feb. 2025
-
Since then, Putin has sought instead to rally the public to the defense of a motherland besieged by the perfidious and cunning West.—
Leon Aron,
The Atlantic,
5 Dec. 2024
Adjective
-
The senators are incorrect three times, and surely more.—
John Tamny,
Forbes.com,
2 June 2025
-
But here’s the twist: both might technically be incorrect.—
Simon Perry,
People.com,
27 May 2025
Adjective
-
Don’t hire a sales person the conventional way Traditional sales hiring focuses on the wrong signals.—
Jodie Cook,
Forbes.com,
30 May 2025
-
There’s no wrong way to have your bowl of pho, said Pho Momma’s owner, My Le.—
Camila Pedrosa,
Sacbee.com,
30 May 2025
Cite this Entry
“Insidious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/insidious. Accessed 13 Jun. 2025.
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